systemd issue in centos 7

Not working pre-create pid-file dir (/run/i2pd).
It fixed with one of this ways:

> PermissionsStartOnly=True
or 
> ExecStartPre=/bin/mkdir -p -m 0700 /var/run/i2pd
> ExecStartPre=/bin/chown i2pd: /var/run/i2pd

First way is prefer because RuntimeDirectory's options already used.

contrib/rpm/i2pd.service

@@ -5,6 +5,7 @@ After=network.target
 [Service]
 User=i2pd
 Group=i2pd
+PermissionsStartOnly=True
 RuntimeDirectory=i2pd
 RuntimeDirectoryMode=0700
 Type=simple